首页 > 代码库 > （转）RGB 与 YUV420 相互转换
（转）RGB 与 YUV420 相互转换
RGB to YUV420 原代码： RGB2YUV.CPP文件
RGB to YUV420 原代码： RGB2YUV.CPP文件
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include<iostream>
//转换矩阵
#define MY(a,b,c) (( a* 0.2989 + b* 0.5866 + c* 0.1145))
#define MU(a,b,c) (( a*(-0.1688) + b*(-0.3312) + c* 0.5000 + 128))
#define MV(a,b,c) (( a* 0.5000 + b*(-0.4184) + c*(-0.0816) + 128))
//大小判断
#define DY(a,b,c) (MY(a,b,c) > 255 ? 255 : (MY(a,b,c) < 0 ? 0 : MY(a,b,c)))
#define DU(a,b,c) (MU(a,b,c) > 255 ? 255 : (MU(a,b,c) < 0 ? 0 : MU(a,b,c)))
#define DV(a,b,c) (MV(a,b,c) > 255 ? 255 : (MV(a,b,c) < 0 ? 0 : MV(a,b,c)))
//只处理352*288文件
#define WIDTH 352
#define HEIGHT 288
//读BMP
void ReadBmp(unsigned char *RGB,FILE *fp);
//转换函数
void Convert(unsigned char *RGB, unsigned char *YUV);
//入口
int main()
{
int i=1;
char file[255];
FILE *fp;
FILE *fp2;
unsigned char *YUV = NULL;
unsigned char *RGB = NULL;
unsigned int imgSize = WIDTH*HEIGHT;
if((fp2 = fopen("test.cif", "wb")) == NULL)//生成文件名
{
return 0;
}
RGB = (unsigned char*)malloc(imgSize*6);
YUV = (unsigned char*)malloc(imgSize + (imgSize>>1));
for(i=1; i<2; i++)
{
sprintf(file, "test.bmp", i);//读取文件
if((fp = fopen(file, "rb")) == NULL)
continue;
printf("打开文件%s\n", file);
ReadBmp(RGB, fp);
Convert(RGB, YUV);
fwrite(YUV, 1, imgSize+(imgSize>>1), fp2);//写入文件
fclose(fp);
}
fclose(fp2);
if(RGB)
free(RGB);
if(YUV)
free(YUV);
printf("完成\n");
system("pause");
return 1;
}
//读BMP
void ReadBmp(unsigned char *RGB,FILE *fp)
{
int i,j;
unsigned char temp;
fseek(fp,54, SEEK_SET);
fread(RGB+WIDTH*HEIGHT*3, 1, WIDTH*HEIGHT*3, fp);//读取
for(i=HEIGHT-1,j=0; i>=0; i--,j++)//调整顺序
{
memcpy(RGB+j*WIDTH*3,RGB+WIDTH*HEIGHT*3+i*WIDTH*3,WIDTH*3);
}
//顺序调整
for(i=0; (unsigned int)i < WIDTH*HEIGHT*3; i+=3)
{
temp = RGB[i];
RGB[i] = RGB[i+2];
RGB[i+2] = temp;
}
}
void Convert(unsigned char *RGB, unsigned char *YUV)
{
//变量声明
unsigned int i,x,y,j;
unsigned char *Y = NULL;
unsigned char *U = NULL;
unsigned char *V = NULL;
Y = YUV;
U = YUV + WIDTH*HEIGHT;
V = U + ((WIDTH*HEIGHT)>>2);
for(y=0; y < HEIGHT; y++)
for(x=0; x < WIDTH; x++)
{
j = y*WIDTH + x;
i = j*3;
Y[j] = (unsigned char)(DY(RGB[i], RGB[i+1], RGB[i+2]));
if(x%2 == 1 && y%2 == 1)
{
j = (WIDTH>>1) * (y>>1) + (x>>1);
//上面i仍有效
U[j] = (unsigned char)
((DU(RGB[i ], RGB[i+1], RGB[i+2]) +
DU(RGB[i-3], RGB[i-2], RGB[i-1]) +
DU(RGB[i -WIDTH*3], RGB[i+1-WIDTH*3], RGB[i+2-WIDTH*3]) +
DU(RGB[i-3-WIDTH*3], RGB[i-2-WIDTH*3], RGB[i-1-WIDTH*3]))/4);
V[j] = (unsigned char)
((DV(RGB[i ], RGB[i+1], RGB[i+2]) +
DV(RGB[i-3], RGB[i-2], RGB[i-1]) +
DV(RGB[i -WIDTH*3], RGB[i+1-WIDTH*3], RGB[i+2-WIDTH*3]) +
DV(RGB[i-3-WIDTH*3], RGB[i-2-WIDTH*3], RGB[i-1-WIDTH*3]))/4);
}
}
}
YUV420 to RGB 原代码： yuv2rgb.cpp文件
#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#define WIDTH 352
#define HEIGHT 288
//转换矩阵
double YuvToRgb[3][3] = {1, 0, 1.4022,
1, -0.3456, -0.7145,
1, 1.771, 0};
//根据RGB三分量写BMP，不必关注
int WriteBmp(int width, int height, unsigned char *R,unsigned char *G,unsigned char *B, char *BmpFileName);
//转换函数
int Convert(char *file, int width, int height, int n)
{
//变量声明
int i = 0;
int temp = 0;
int x = 0;
int y = 0;
int fReadSize = 0;
int ImgSize = width*height;
FILE *fp = NULL;
unsigned char* yuv = NULL;
unsigned char* rgb = NULL;
unsigned char* cTemp[6];
char BmpFileName[256];
//申请空间
int FrameSize = ImgSize + (ImgSize >> 1);
yuv = (unsigned char *)malloc(FrameSize);
rgb = (unsigned char *)malloc(ImgSize*3);
//读取指定文件中的指定帧
if((fp = fopen(file, "rb")) == NULL)
return 0;
fseek(fp, FrameSize*(n-1), SEEK_CUR);
fReadSize = fread(yuv, 1, FrameSize, fp);
fclose(fp);
if(fReadSize < FrameSize)
return 0;
//转换指定帧 如果你不是处理文件 主要看这里
cTemp[0] = yuv; //y分量地址
cTemp[1] = yuv + ImgSize; //u分量地址
cTemp[2] = cTemp[1] + (ImgSize>>2); //v分量地址
cTemp[3] = rgb; //r分量地址
cTemp[4] = rgb + ImgSize; //g分量地址
cTemp[5] = cTemp[4] + ImgSize; //b分量地址
for(y=0; y < height; y++)
for(x=0; x < width; x++)
{
//r分量
temp = cTemp[0][y*width+x] + (cTemp[2][(y/2)*(width/2)+x/2]-128) * YuvToRgb[0][2];
cTemp[3][y*width+x] = temp<0 ? 0 : (temp>255 ? 255 : temp);
//g分量
temp = cTemp[0][y*width+x] + (cTemp[1][(y/2)*(width/2)+x/2]-128) * YuvToRgb[1][1]
+ (cTemp[2][(y/2)*(width/2)+x/2]-128) * YuvToRgb[1][2];
cTemp[4][y*width+x] = temp<0 ? 0 : (temp>255 ? 255 : temp);
//b分量
temp = cTemp[0][y*width+x] + (cTemp[1][(y/2)*(width/2)+x/2]-128) * YuvToRgb[2][1];
cTemp[5][y*width+x] = temp<0 ? 0 : (temp>255 ? 255 : temp);
}
//写到BMP文件中
sprintf(BmpFileName, "test.bmp", file, n);
WriteBmp(width, height, cTemp[3], cTemp[4], cTemp[5], BmpFileName);
free(yuv);
free(rgb);
return n;
}
//入口 没啥东西
void main()
{
int i=1;
// for( i=0; i<260; i++)
Convert("test.cif", WIDTH, HEIGHT, i);//调用上面的Convert,获取文件的第i帧
}
//写BMP 不必关注
int WriteBmp(int width, int height, unsigned char *R,unsigned char *G,unsigned char *B, char *BmpFileName)
{
int x=0;
int y=0;
int i=0;
int j=0;
FILE *fp;
unsigned char *WRGB;
unsigned char *WRGB_Start;
int yu = width*3%4;
int BytePerLine = 0;
yu = yu!=0 ? 4-yu : yu;
BytePerLine = width*3+yu;
if((fp = fopen(BmpFileName, "wb")) == NULL)
return 0;
WRGB = (unsigned char*)malloc(BytePerLine*height+54);
memset(WRGB, 0, BytePerLine*height+54);
//BMP头
WRGB[0] = ‘B‘;
WRGB[1] = ‘M‘;
*((unsigned int*)(WRGB+2)) = BytePerLine*height+54;
*((unsigned int*)(WRGB+10)) = 54;
*((unsigned int*)(WRGB+14)) = 40;
*((unsigned int*)(WRGB+18)) = width;
*((unsigned int*)(WRGB+22)) = height;
*((unsigned short*)(WRGB+26)) = 1;
*((unsigned short*)(WRGB+28)) = 24;
*((unsigned short*)(WRGB+34)) = BytePerLine*height;
WRGB_Start = WRGB + 54;
for(y=height-1,j=0; y >= 0; y--,j++)
{
for(x=0,i=0; x<width; x++)
{
WRGB_Start[y*BytePerLine+i++] = B[j*width+x];
WRGB_Start[y*BytePerLine+i++] = G[j*width+x];
WRGB_Start[y*BytePerLine+i++] = R[j*width+x];
}
}
fwrite(WRGB, 1, BytePerLine*height+54, fp);
free(WRGB);
fclose(fp);
return 1;
}
转自：http://ctfysj.blog.hexun.com/14194936_d.html